Degumming method

Abstract

A method for producing membrane polysaccharides from an organism selected from micro-organisms, unicellular organisms and filamentous fungi, the method including at least one step of extracting the membrane polysaccharides as well as a smaller-scale extraction of the soluble proteins, by mechanical treatment of the organism in a ball mill or by physical treatment of the organism by means of ultrasounds.

The invention claimed is: 
     
       1. A process for obtaining membrane polysaccharides from an organism selected from microorganisms, unicellular organisms and filamentous fungi, wherein the process comprises at least one step of extracting the membrane polysaccharides, accompanied by a reduced extraction of the soluble proteins, by mechanical treatment of the organism in a ball mill or by physical treatment of the organism by means of ultrasound, and wherein:
 the process is performed by mechanical treatment using a ball mill equipped with glass balls under the following conditions:
 a mean diameter of the balls (d GM ) ranges from 1.5×10 −3  to 2.5×10 −3  m, and 
 a stirring speed at a blade end (v) ranges from 5 to 20 m·sec −1 , or 
 
 the process is performed by physical treatment by means of ultrasound under the following conditions:
 an energy of the ultrasound ranges from 500 to 5000 J, 
 a power of the ultrasound ranges from 200 W to 400 W, and 
 a feed flow rate ranges from 0.150 l/min to 3 l/min. 
 
 
     
     
       2. The process as claimed in  claim 1 , wherein the process is performed by the mechanical treatment using the ball mill equipped with glass balls. 
     
     
       3. The process as claimed in  claim 2 , wherein the mechanical treatment using the ball mill is carried out for a period ranging from 2 to 50 minutes. 
     
     
       4. The process as claimed in  claim 2 , wherein a ball filling rate of the mill ranges from 60% to 80% volume/volume. 
     
     
       5. The process as claimed in  claim 1 , wherein the process is performed by the physical treatment using ultrasound. 
     
     
       6. The process as claimed in  claim 5 , wherein the ultrasound treatment is carried out for a period ranging from 5 to 30 seconds. 
     
     
       7. The process as claimed in  claim 1 , wherein the mechanical or physical treatment step is followed by a step of measuring an amount of membrane polysaccharides extracted. 
     
     
       8. The process as claimed in  claim 1 , wherein at least one treatment step is followed by a step of measuring an amount of membrane polysaccharides that have been extracted. 
     
     
       9. The process as claimed in  claim 1 , wherein the organism is selected from cyanobacteria, microalgae, bacteria and filamentous fungi. 
     
     
       10. The process as claimed in  claim 1 , wherein the organism is selected from: the division Rhodophyta and from the genera  Porphyridium  and  Rhodella, Spirulina  and  Dunaliella.    
     
     
       11. The process as claimed in  claim 1 , wherein it comprises a step consisting in extracting the soluble polysaccharide fraction from a medium. 
     
     
       12. The process as claimed in  claim 1 , wherein the membrane polysaccharide extraction step is followed by a step of purifying the polysaccharides.